Lubricant



Patented Nov. 28,- 1944 OFFICE LUBRICANT John A. Patterson, Beacon, N. Y., asslznor to The Texas Company, New York, N. Y., a corporation or Delaware No Drawing. Application mam 28, 1942,

, Serial No. 432,790

Claims. (01. 252-35) the Anacardium genus of the Anacardiaceae family in .hydrocarbon oils, particularly petroleum oil, to improve the properties of lubricants compounded therewith.

The additive ingredients of the present invention are prepared from the naturally occurring oils which fall within the classification of the Anacardium genus of the Anacardiaceae family and include the compositions and constituents of cashew nut shell oil, marking nut shell oil and Japanese lac. ties on these naturally occurring oils that the chemical composition thereof consists primarily of mixtures of various typesof aromatic derivatives such as anacardic acid (C22Ha20a), cardol' (C32H5204), anacardol (C1sH3oO), and urushiol (CzoHaoOz).

Cashew nut shell oil, 'as described by M. T.-

Harvey and S. Caplan in Industrial and Engineering Chemistry, vol. 32, No.10, pages 1306-1310, contains approximately 90% anacardic acid and It is the consensus of the authori- 10% cardol when extracted from the shells by means ofsolvents. However, when the extraction of the oil is carried out by a thermal-process,

the extracted oil contains only about 16% anacardic acid. The balance of the heat-treated oil consists of a mixture of cardanol (CzoI-IszO), cardol and a residue of degradation products. The difference in composition of the two oils resulting from the solvent and thermal extraction process indicates the high degree of instability of the natural occurring oil. emplified by the fact that during storage the solvent extracted oil undergoes some reaction change as evidenced by the evolution of carbon dioxide. The physical constants of a representative sample of the solvent extracted oil are as carbon oils used in the lubricating systems thereof. Thus the increase in operating temperatures and engine speeds, together with reduced clearances between the moving parts and the use of hard-bearing alloys, such as copper-lead, cadmium-silver, etc. have seriously accentuated such 7 problems as corrosion, oxidation, and varnish and lacquer-formation with the resultant deleterious effect on the'efllciency of the equipment.

It has been discoveredthat the addition of an oil-soluble or oil-miscible metal derivative of a composition obtained or derived from the Anacardium genus of theAnacardiaceae family to a refined hydrocarbon oil provides a lubricant or a compounding lubricant which possesses improved resistance to oxidation as measured by the decrease in sludge, varnish and lacquer formation of the hydrocarbon all during service. The refined hydrocarbon oils which may be improved by the compositions of the present inven tion include the petroleum lubricating oils, such as used in aviation oils, industrial lubricants, greases, textile oils, etc.

In preparing the metal derivatives of the Anacardium oils, care must be taken to avoid poly.- merization and other internal reactions. The

' preferred method ofpreparation is to react the This is furtherexfollows: 1

Bromine No 93 Hydroxyl No- 180 Neutralization No. (A. S. T. M. A-) 95 Saponification No. (A. S. T. M. B 98 The compounds contained in the oil apparently possess one ,or more hydroxyl (OH) and carboxyl (COOH) groups together with unsaturated radiwardlthe'ji'nre'ase in power output-("and efliciency of mechanical-equipment have set up such severe and exacting operating conditions as to necessitate animprovement in the highly refined hydrooil with a'solution of the desired metal or a metal salt in liquid ammonia. When using a solution of a metal in liquid ammonia, the reaction apparently tends to stabilize the oil, due to the resulting partial hydrogenation of the unsaturated constituents by means of the residual hydrogen displaced by the metal, as evidenced by the decrease in bromine number. When using a solution of the metal salt such as the halide in liquid ammonia, no hydrogenation takes place and, therefore, the particular method used will depend upon the desirability of decreasing the unsaturation of the compositions. However, the invention is not limited to these particular methods of preparing the metal derivatives and any other classical methods may be used which result in the formation of oil-soluble or oil-miscible metal derivatives.

The degree of neutralization may be varied according to the amount of metal or metal salt rebe neutralized to form the corresponding metal derivative.

In some of the oils, it may be desirable to lower the tendency toward condensation and polymerization by completely, or partially, hydrogenating the unsaturated constituents prior to theformation of the metal derivatives. Further, inorganic substituents such as sulfur, halogen, nitrogen and phosphorus may be incorporated in the oils to increasethe solubility or improving qualities of the compositions. As an example, the anticorrosive properties of the additive may be improved by adding sulfur to the compositions in the form of a sulfide, thio-ether, mercaptan, etc.

It is to be understood that the term metal derivative of compositions obtained or derived from the Anacardium genus of the Anacardiaceae family when used throughout the specification and claims is meant to include the metal derivatives, e. g., the partial or completely neutralized reactive hydroxyl and/or carboxyl groups, of the compositions contained in the oils falling within the classification of the Anacardium genus of the Anacardiaceae family and including cashew nut shell oil, marking nut shell oil, Japanese lac, etc., together with the hydrogenated and/or further derivatives thereof containing sulfur, halogen, nitrogen, and phosphorus substituents.

The particular metals which may be used to' form the oil-soluble metal derivatives of the presprovement desired in the hydrocarbon oil. The

preferred range of proportions in a mineral lubricating oil when used in a few of the more common services are as follows:

Per cent by weight of finished lubricant Diesel lubricating oil 0.5 -1.0 Motor lubricating oil 0.3 -0.6 Heavy duty lubricating oil 0.5 -2.5 Turbine lubricating oil 0.010.l Airplane lubricating oil 0.2 -0.6

Of the Anacardium oils previously mentioned, cashew nut shell oil is preferred and the present invention is particularly concerned with the solvent extracted oil which consists primarily of anacardic acid and cardol. This solvent extracted oil appears as a black, viscous oil which itself is only slightly soluble and forms a hazy solution in a mineral lubricating oil. The following example i an illustration of the preparation of one of the simpler metal derivatives of the present invention:

Example 300 grams of solvent extracted cashew nut shell oil was dissolved in toluene and added 5 wly to a solution of grams of anhydrous s nnous chloride in 2.5 liters of liquid ammonia with vigorous agitation. After the addition was complete, the ammonia was allowed to boil off. Additional toluene was then added and the solution warmed and filtered. The remaining toluene was then removed from the filtrate by heating in vacuo. The resulting tin derivative was converted to a 25% concentrate by; dissolving it in three times its weight of the mineral lubricating oil. The 25 concentrate analyzed 5.75% tin.

Other metal salts or metals may be used in place of the stannous chloride of this example and the oil may be subjected to complete or partial hydrogenation and/or reacted with other constituents to incorporate additional improving properties in the former sulfur, chlorine, nitrogen anclphosphorus containing radicals either prior or subsequent to neutralization with the metal.

The unusual effectiveness of the compounds of the present invention when incorporated in a mineral lubricating oil was demonstrated by practical tests in an actual automotive engine. This test was run in a standard Chevrolet engine operated on a block for 40 hours at 2500 R. P. M.

and 50 M. P. H. or an equivalent of 2000 miles with a crankcase oil temperature of 275 F. and jacket temperature of 212 F. with a, crankcase ventilation of one cubic foot of air per minute. The test was stopped at a 10-hour period and started immediately. At 20 hours, the engine was stopped and rested for four hours. At 30 hours, the engine was again stopped and rested for four hours. At 40 hours, the test was halted, the engine was taken down. the pistons removed and the amount of varnish deposit determined on the oil rings, piston skirt, rocker arm, valve cover plate and pan. This was accomplished in each case by washing first with precipitation naphtha to remove the retained oil, then washing with acetone to remove the bulk of the varnish deposit. The acetone solution was then evaporated to dryness and the residue extracted with precipitation naphtha to remove the remaining traces of oil. The residue was again taken up in an acetone solution and filtered to remove suspended deposits and finally evaporated to dryness. The' weight of the varnish deposit was expressed as milligrams acetone soluble and milligrams acetone insoluble. The acetone insoluble portion was that portion of the varnish which was filtered out of the acetone solution.

A further test was run on the used oil to determine the amount of deterioration of the oil as measured by the amount of sludge present, neutralization number change and increase in viscosity. The following results were obtained on an inhibited reference oil which was a solvent-refined, dewaxed, Mid-Continent lubricating oil of an SAE 20 grade, together with said oil, containing the thin derivative of cashew nut shell oil as prepared in the foregoing example:

aaeaeee Used oil analysis Undls- Dis- Neut. B. U. vise solved solved No. @210F sludge, sludge,

mgs. mgs.

Reference oil i 2 71 142 303 Reference oil+0.5% tin derivative of cashew nut shell oll (Example) 4.7 64 A 152 156 The hydrocarbon oils to which the oil-soluble metal derivatives of the present invention are added may be either in the crude form or partially or highly refined and may contain other additive ingredients such as dyes, metal soaps, pour depressants, thiclreners, V. I. improvers, oiliness agents, extreme pressure agents, sludge dispersers, oxidation inhibitors, and corrosion inhibitors such as sulfurized hydrocarbons, etc.

Obviously many modifications and variations of the invention, as hereinbefore set forth, may Ibe made without departing from the spirit and scope thereof and, therefore, only such limitations should be imposed as are indicated in the appended claims. l

I claim: 7

l. A lubricant comprising a hydrocarbon oil and a small quantity, sufiicient to impart oxidationresistant properties to said oil, of an oil-soluble metal derivative of cashew nut shell oil.

2. A lubricant comprising a mineral lubricating oil and a small quantity, sufilcient to impart oxidation-resistant properties to said oil, of an oilsoluble metal derivative of cashew nut shell oil.

3. A lubricant comprising a hydrocarbon oil having incorporated therein (Ml-5.0% of an oilsoluble metal derivative of cashew nut shell oil.

4. A lubricant comprising a mineral lubricating oil having incorporated therein 0.2-2.5% of an oilsoluble metal derivative of solvent extracted cashew nut shell oil.

5. A lubricant comprising a mineral lubricating oil and 0.01-5.0% by weight 01' an oil-soluble tin derivative of cashew'nut shell oil.

6. A lubricant comprising a hydrocarbon oil and a small quantity, sufllcient to impart oxidationresistant properties to said oil, of an oil-soluble metal derivative of the aromatic components of an oil extracted from a member of the Anacardium genus of. the Anacardiaceae family. 7. A lubricant comprising a hydrocarbon oil and'0.0l-5.0% by weight of an oil-soluble metal derivative of the aromatic components of an oil extracted from a member of the Anacardium genus of the Anacardiaceae family, said oil being extracted by solvent extraction.

8. A lubricant comprising a mineral lubricating oil and Mil-5.0% by weight of an oil-soluble metal derivative of the aromatic components of an oil extracted from a member of the Anacar-' dium genus of the Anacardiaceae family.

9. A lubricant comprising a hydrocarbon oil having incorporated therein Mil-5.0% of an oilsoluble metal derivative of the aromatic components of an oil extracted from a member of the Anacardium genus of the Anacardiaceae family.

10. A compounding lubricant comprising a hydroearbon oil and a quantity, suilicientto impart oxidation-resistant properties to the lubricants compounded therewith, of an oil-soluble metal derivative of the aromatic components of an oil extracted from a member of the Anacardium genus of the Anacardiaceae family.

JOHN A. PATTERSON. 

